The subject matter disclosed herein generally relates to lubrication and cooling of electrical machines, and more particularly to hybrid cascading lubrication and cooling for an electrical machine with nested stages.
An electrical machine may include one or more stages arranged sequentially along a shaft as a rotor assembly. To cool the electrical machine, cooling oil can be pumped into the inside diameter of the shaft. The cooling oil flows through the rotor assembly to remove heat. The cooling oil can be pressurized and sprayed directly from the shaft to cool components in close physical proximity to the shaft. However, such a cooling and lubrication scheme may be ineffective if cooling oil cannot be pumped through the shaft or components to be cooled are not directly reachable by spray from the shaft.